package com.huaishushu.filter;


import com.alibaba.fastjson2.JSON;
import com.huaishushu.common.BaseContext;
import com.huaishushu.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * @Author HuaiShuShu
 * @Date 2023/5/28 21:56
 * @PackageName:com.huaishushu.filter
 * @Description: 过滤器，过滤url请求。
 * @Version 1.0
 */
@Slf4j
@WebFilter(filterName = "LoginCheckFilter",urlPatterns = "/*")
public class LoginCheckFilter implements Filter {
    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;
        //1、获取本次请求的URI
        String requestURI = request.getRequestURI();
        log.info("拦截到请求：{}",requestURI);

        //定义不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/user/sendMsg", //移动端发送短信
                "/user/login" //移动端登录
        };
        //2、判断本次请求是否需要处理
        boolean check = check(urls, requestURI);
        // 3、如果不需要处理，则直接放行
        if (check) {
            filterChain.doFilter(request,response);
            return;
        }
        // 4-1、判断登录状态，如果已登录，则直接放行
        if (request.getSession().getAttribute("employee") != null) {
            log.info("用户已登录，登录id：" + request.getSession().getAttribute("employee"));

            //设置线程局部变量，供公共字段自动填充用
            Long empId = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

            filterChain.doFilter(request, response);
            return;
        }
        // 4-2、判断登录状态，如果已登录，则直接放行
        if (request.getSession().getAttribute("userId") != null) {
            log.info("移动端用户已登录，用户id为：" + request.getSession().getAttribute("userId"));

            //设置线程局部变量，供公共字段自动填充用
            Long userId = (Long) request.getSession().getAttribute("userId");
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request, response);
            return;
        }
        // 5、如果未登录则返回未登录结果，通过输出流方式向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("用户未登录，跳转到登录页")));
        log.info("用户未登录，跳转到登录页");
        //request.getRequestDispatcher("/backend/page/login/login.html").forward(request,response);
        return;
    }

    /**
     * 路径匹配，检查本次请求是否需要放行
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls,String requestURI) {
        for (String url : urls) {
            //逐一进行匹配，如果匹配上了则直接返回true
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match) {
                return true;
            }
        }
        return false;
    }

}
